Features:  This control panel of the spot welding machine is independently developed for the DIY or the simple resistance welding.   The principle of silicone controlled phase triggering is adopted to adjust the time and the current to achieve the purpose of welding.  Equipped with digital display, you can see the time and current directly, simple and easy to use.  Strong and weak electricity is isolated by optocoupler, safer to operate.  Using high precisions single bit potentiometer, to ensure reliable and convenient input.  A reliable zero-crossing detection circuit to ensure that the SCR phase accurate.  Comes with a quality foot pedal, wear resistant and can provide long service time.  There are two type 9V 40A or 9V 100A for choose you to choose according to your demands.    Specifications:  Name: Spot Welding Tool Set  Type: 9V 40A, 9V 100A (optional)  Package size: 175 * 95 * 115mm / 6.89 * 3.74 * 4.53in  Package weight: 460g / 1.01lb    Packing List:  1 * Spot Welding Tool Set